Fingerprints are unique and permanent features distinguishing one person from another. Often, a fingerprint includes a plurality of ridges and grooves on the skin of a finger. The patterns formed by the ridges and grooves often include ridge bifurcation, ridge ends, arches, tented arches, left-handed spiral whorls, right-handed spiral whorls, ulnar loops, double loops, etc., which determine the uniqueness of the fingerprint patterns. The fingerprint identification technologies developed based on the features of the fingerprints are used relatively early for personal identification verification. According to different ways of fingerprint collection and fingerprint input, the well-known and widely used fingerprint identification technologies include optical imaging, thermal sensing, human body far infrared sensing, etc.
Currently, touch screens with touch functions integrated into liquid crystal pixels, i.e., in-cell touch functions, have become popular because of advantages such as low fabrication cost and thin device volume. In existing touch technologies, the in-cell touch functions are implemented by attaching a touch film on a thin-film transistor-liquid crystal display (TFT-LCD) panel. The touch film senses touch motions so that the LCD panel and the touch film are driven separately to implement functions. However, the disadvantages of the above-mentioned structure include the display panel being bulky and heavy. Also, the touch film needs to be fabricated separately, which requires additional fabrication cost. The attaching or bonding process also increases the fabrication cost of the display screen.
Further, the existing touch technologies used in the screens of mobile phones or tablets often only recognize touch motions by a finger or a conductive stylus. As the market development of mobile payment and information security, fingerprint recognition is becoming more and more important.
Thus, it is desirable to improve the resolution of the in-cell touch screens with fingerprint recognition functions in exiting touch technologies.